update Microsoft surprised developers on Monday by releasing a test version of a new Windows file system.

The company made the test version of the system, called WinFS, available to Microsoft Developer Network subscribers. The software giant had originally planned to release WinFS--which it said would make for better desktop file searching--as part of the next version of Windows, once called Longhorn but now known as Vista. However, roughly a year ago, Microsoft announced it was pulling WinFS out of Longhorn in order to let the OS ship in 2006. Of WinFS, the company said only that it would be in beta form by the time Longhorn shipped.